This Phase I SBIR program will produce a computational electromagnetics (CEM) tool to efficiently determine high fidelity solutions for arbitrarily configured ESAs and for the optimization of ESAs in electromagnetically varying environments. Two CEM technologies would be used: a state-of-the-art preconditioned, MLFMA-accelerated integral equation solver, and a revolutionary fast CEM direct solver. The fast iterative CEM model will provide a state-of-the-art CEM baseline which will be augmented to incorporate fast, direct CEM solution methods based on LOGOS simulation technologies. The LOGOS framework provides a new, general, physics-based structure for modular, fast, direct, broadband numerical simulations for fields in complex environments; it is based on the systematic, numerically efficient application of a fundamentally new organizing principle for fast, direct electromagnetic simulations at all frequencies. It provides new capabilities essential to an efficient ESA optimization tool including the ability to develop controllable, reduced-order models for the electromagnetic response of complex systems, and an ability to perform perturbative design within very large scenes. Consequently, the proposed tool will provide dramatic computational savings relative to existing CEM technologies in modeling ESA performance in the presence of environmental perturbations. NanoSonic will accomplish the proposed effort with a major research university and a prime defense contractor.